Lawn and Garden
Subsurface residential lawn irrigation system with Netafim® CV
It's not the easiest balancing act. Even if you follow all of the suggestions and watering restrictions, the water bill keeps going up and your lawn still turns brown.
Normal lawn watering methods just don't work very well in Colorado. We have a semi-arid climate, so watering with any type of system that sprays the water into the air does a great job of cooling the air (through evaporation), but not such a great job of providing the necessary moisture to the grass. Much of the ground in the area has a high percentage of clay, so the water doesn’t soak in very fast. A standard pop-up sprayer puts out water at twice the rate that the lawn can absorb it. The extra water just sits on the surface and evaporates or runs into the gutter. On windy days your sprinkler system may put as much water in the street or on your neighbor’s lawn as on your own. Sloping property can be dry at the top and soggy at the bottom. Generally speaking, only about 60% of the water that you spray at your lawn actually provides moisture to your grass.
Until recently, spraying your valuable water into the air and hoping it landed where it was aimed was the only method available to the average homeowner. Recent advances in subsurface irrigation technology and installation techniques have changed all this. Subsurface irrigation provides the precise amount of water needed directly to the root growth area of your lawn. Evaporation from the sun and wind is dramatically reduced because the surface of the ground isn’t getting wet. There are specific styles of irrigation tubing developed specifically for clay, loam or sandy soils, so you just select the correct style for your soil conditions. Subsurface irrigation delivers 90% of the water you apply directly to your lawns root system.
If you had considered subsurface irrigation even a few years ago, you were probably discouraged by the expense and complexity of the installation. In the past four to five years some dramatic improvements have been made in both the materials and installation techniques. These improvements have reduced the cost significantly and made installation almost as easy as the traditional aboveground spray systems. With subsurface irrigation, the water is applied at a slower rate but for a longer period of time. The slower application rate means that your sprinkler zones can be significantly larger. For example, a medium sized yard might need 8 zones with an aboveground system. The subsurface irrigation system might only need 3 or 4 zones. Fewer zones mean fewer control valves, smaller manifold and a less expensive timer. All of these things can add up to significant cost savings.
OK, I’m interested.
Good. Now it is time to do some research. Several of the major sprinkler manufacturers now make drip and subsurface components. Check out their web sites and compare features. One highly recommended site is www.netafimusa.com. While you may not recognize their name, Netafim® is the pioneer in low volume irrigation. They have been in the business since the 1960’s and have been instrumental in the development of subsurface, on-surface and point source (drip) irrigation. Their products are sold in over 80 countries worldwide. Netafim® recently introduced the Techline® CV (the “CV” stands for “Check Valve”) product line which eliminates much of the cost and complexity associated with earlier systems. The check valve keeps the water in the tubing system when the system is off. It also eliminates the need for a purge valve and air/vacuum relief valves, (a requirement in older systems). Just these two improvements save an average of 3 gallons of water per zone each time the system is turned on. While that may not sound like much, over the course of a watering season it can save you thousands of gallons of water.
Subsurface installations in new lawns can be installed in much the same manner as above ground systems. The tubing is placed in parallel, evenly spaced rows on the ground and covered to the proper depth (4 to 6 inches). If you won’t be adding that much fill, a series of shallow trenches can be dug in the same parallel row pattern or you can use a pipe puller to install the tubing at the correct depth. Roll on the turf and you are done. There are no sprinkler heads to step on or get knocked off when you cut the grass.
Surprisingly enough, installing a new subsurface irrigation system or replacing a leaky or worn out sprinkler system in an existing lawn is easier than you might think. The new system can usually be installed right over the top of the old system, since the old pipes are generally deeper in the ground than the new pipes. One shallow trench at each end of the yard is all the digging that is needed. The subsurface tubing is pulled from one end of the yard to the other, with minimal turf damage. We have had great success with the Lineward® L2 pipe puller www.lineward.com. It is very maneuverable and easy to use and operate. Plus, it has rubber treads instead of tires so it doesn’t leave tire tracks in the yard. After the pipe is pulled and connected and the trench’s are covered, it is difficult to tell that any work been done in the yard.
It is in everyone's best interest to conserve water whenever possible. Since a subsurface irrigation system can save you from 30 to 70 percent in lawn water usage, it can benefit the environment as well as your bank account. So, if a new or upgraded sprinkler system is in your plans, you may want to give a subsurface system a good look. Give us a call and we will be happy to answer any questions you may have.
Chris Price is the Store Manager at CJ&J Sprinkler and Pond Supply
418 8th St. South East, Loveland CO 80537 (970) 278-1999 and on the Internet at www.cjjstore.com